/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.    
 */
using System;
using Parser = Velocity4Net.Runtime.Parse.Parser;
using MethodInvocationException = Velocity4Net.Errors.MethodInvocationException;
using InternalContextAdapter = Velocity4Net.Ctx.InternalContextAdapter;
namespace Velocity4Net.Runtime.Parse.AST
{

    /// <summary> Handles integer multiplication
    /// *
    /// Please look at the Parser.jjt file which is
    /// what controls the generation of this class.
    /// *
    /// </summary>
    /// <author> <a href="mailto:jvanzyl@apache.org">Jason van Zyl</a>
    /// </author>
    /// <author> <a href="mailto:geirm@optonline.net">Geir Magnusson Jr.</a>
    /// </author>
    /// <version> $Id: ASTMulNode.cs,v 1.3 2003/10/27 13:54:10 corts Exp $
    /// </version>
    public class ASTMulNode : SimpleNode
    {
        public ASTMulNode(int id) : base(id) { }

        public ASTMulNode(Parser p, int id) : base(p, id) { }

        /// <summary>  computes the product of the two args.  Returns null if either arg is null
        /// or if either arg is not an integer
        /// </summary>
        public override System.Object GetValue(InternalContextAdapter context)
        {
            /*
            *  get the two args
            */

            System.Object left = jjtGetChild(0).GetValue(context);
            System.Object right = jjtGetChild(1).GetValue(context);

            /*
            *  if either is null, lets log and bail
            */

            if (left == null || right == null)
            {
                rsvc.error((left == null ? "Left" : "Right") + " side (" + jjtGetChild((left == null ? 0 : 1)).Literal() + ") of multiplication operation has null value." + " Operation not possible. " + context.CurrentTemplateName + " [line " + Line + ", column " + Column + "]");
                return null;
            }

            /*
            *  if not an Integer, not much we can do either
            */

            if (!(left is System.Int32) || !(right is System.Int32))
            {
                rsvc.error((!(left is System.Int32) ? "Left" : "Right") + " side of multiplication operation is not a valid type. " + "Currently only integers (1,2,3...) and Integer type is supported. " + context.CurrentTemplateName + " [line " + Line + ", column " + Column + "]");

                return null;
            }

            return ((System.Int32)left) * ((System.Int32)right);
        }
    }
}
